Added new fields to the ARTMessage.

Source/ARTBaseMessage.m

@@ -21,6 +21,7 @@ - (id)copyWithZone:(NSZone *)zone {
     message->_data = [self.data copy];
     message->_connectionId = self.connectionId;
     message->_encoding = self.encoding;
+    message->_extras = self.extras;
     return message;
 }
 

Source/ARTJsonLikeEncoder.m

@@ -75,11 +75,11 @@ - (NSString *)formatAsString {
 }
 
 - (ARTMessage *)decodeMessage:(NSData *)data error:(NSError **)error {
-    return [self messageFromDictionary:[self decodeDictionary:data error:error]];
+    return [self messageFromDictionary:[self decodeDictionary:data error:error] protocolMessage:nil];
 }
 
 - (NSArray *)decodeMessages:(NSData *)data error:(NSError **)error {
-    return [self messagesFromArray:[self decodeArray:data error:error]];
+    return [self messagesFromArray:[self decodeArray:data error:error] protocolMessage:nil];
 }
 
 - (NSData *)encodeMessage:(ARTMessage *)message error:(NSError **)error {
@@ -266,7 +266,15 @@ - (NSArray *)decodeStats:(NSData *)data error:(NSError **)error {
     return [self statsFromArray:[self decodeArray:data error:error]];
 }
 
-- (ARTMessage *)messageFromDictionary:(NSDictionary *)input {
+- (nullable NSString *)versionFromInput:(NSDictionary *)input withProtocolMessage:(nullable ARTProtocolMessage *)protocolMessage {
+    if (protocolMessage.channelSerial == nil) {
+        return nil;
+    }
+    int index = [[input artNumber:@"_index"] intValue];
+    return [NSString stringWithFormat:@"%@:%03d", protocolMessage.channelSerial, index]; // TM2p <channelSerial>:<padded_index>
+}
+
+- (ARTMessage *)messageFromDictionary:(NSDictionary *)input protocolMessage:(ARTProtocolMessage *)protocolMessage {
     ARTLogVerbose(_logger, @"RS:%p ARTJsonLikeEncoder<%@>: messageFromDictionary %@", _rest, [_delegate formatAsString], input);
     if (![input isKindOfClass:[NSDictionary class]]) {
         return nil;
@@ -275,24 +283,34 @@ - (ARTMessage *)messageFromDictionary:(NSDictionary *)input {
     ARTMessage *message = [[ARTMessage alloc] init];
     message.id = [input artString:@"id"];
     message.name = [input artString:@"name"];
+    message.action = ([input artNumber:@"action"] ?: [[NSNumber alloc] initWithInt:ARTMessageActionCreate]).integerValue;
+    message.version = [input artString:@"version"] ?: [self versionFromInput:input withProtocolMessage:protocolMessage]; // TM2p
+    message.serial = [input artString:@"serial"];
+    if (!message.serial && message.action == ARTMessageActionCreate) { // TM2k
+        message.serial = message.version;
+    }
     message.clientId = [input artString:@"clientId"];
     message.data = [input objectForKey:@"data"];
-    message.encoding = [input artString:@"encoding"];;
+    message.encoding = [input artString:@"encoding"];
     message.timestamp = [input artTimestamp:@"timestamp"];
+    message.createdAt = [input artTimestamp:@"createdAt"];
+    if (!message.createdAt && message.action == ARTMessageActionCreate) { // TM2o
+        message.createdAt = message.timestamp;
+    }
     message.connectionId = [input artString:@"connectionId"];
     message.extras = [input objectForKey:@"extras"];
 
     return message;
 }
 
-- (NSArray *)messagesFromArray:(NSArray *)input {
+- (NSArray *)messagesFromArray:(NSArray *)input protocolMessage:(ARTProtocolMessage *)protocolMessage {
     if (![input isKindOfClass:[NSArray class]]) {
         return nil;
     }
 
     NSMutableArray *output = [NSMutableArray array];
     for (NSDictionary *item in input) {
-        ARTMessage *message = [self messageFromDictionary:item];
+        ARTMessage *message = [self messageFromDictionary:item protocolMessage:protocolMessage];
         if (!message) {
             return nil;
         }
@@ -734,8 +752,6 @@ - (ARTProtocolMessage *)protocolMessageFromDictionary:(NSDictionary *)input {
     message.id = [input artString:@"id"];
     message.msgSerial = [input artNumber:@"msgSerial"];
     message.timestamp = [input artTimestamp:@"timestamp"];
-    message.messages = [self messagesFromArray:[input objectForKey:@"messages"]];
-    message.presence = [self presenceMessagesFromArray:[input objectForKey:@"presence"]];
     message.connectionKey = [input artString:@"connectionKey"];
     message.flags = [[input artNumber:@"flags"] longLongValue];
     message.connectionDetails = [self connectionDetailsFromDictionary:[input valueForKey:@"connectionDetails"]];
@@ -747,6 +763,17 @@ - (ARTProtocolMessage *)protocolMessageFromDictionary:(NSDictionary *)input {
         message.error = [ARTErrorInfo createWithCode:[[error artNumber:@"code"] intValue] status:[[error artNumber:@"statusCode"] intValue] message:[error artString:@"message"]];
     }
 
+    NSMutableArray *messages = [[input objectForKey:@"messages"] mutableCopy];
+
+    // There is probably a better way to do this, but I have limited time to implement TM2p
+    for (int i = 0; i < messages.count; i++) {
+        NSMutableDictionary *msgDict = [messages[i] mutableCopy];
+        msgDict[@"_index"] = @(i);
+        messages[i] = msgDict;
+    }
+    message.messages = [self messagesFromArray:messages protocolMessage:message];
+    message.presence = [self presenceMessagesFromArray:[input objectForKey:@"presence"]];
+
     return message;
 }
 

Source/ARTMessage.m

@@ -40,7 +40,8 @@ - (NSString *)description {
 - (id)copyWithZone:(NSZone *)zone {
     ARTMessage *message = [super copyWithZone:zone];
     message.name = self.name;
-    message.extras = self.extras;
+    message.action = self.action;
+    message.serial = self.serial;
     return message;
 }
 
@@ -67,7 +68,7 @@ + (instancetype)fromEncoded:(NSDictionary *)jsonObject channelOptions:(ARTChanne
         return nil;
     }
 
-    ARTMessage *message = [jsonEncoder messageFromDictionary:jsonObject];
+    ARTMessage *message = [jsonEncoder messageFromDictionary:jsonObject protocolMessage:nil];
 
     NSError *decodeError = nil;
     message = [message decodeWithEncoder:decoder error:&decodeError];
@@ -97,7 +98,7 @@ + (instancetype)fromEncoded:(NSDictionary *)jsonObject channelOptions:(ARTChanne
         return nil;
     }
 
-    NSArray<ARTMessage *> *messages = [jsonEncoder messagesFromArray:jsonArray];
+    NSArray<ARTMessage *> *messages = [jsonEncoder messagesFromArray:jsonArray protocolMessage:nil];
 
     NSMutableArray<ARTMessage *> *decodedMessages = [NSMutableArray array];
     for (ARTMessage *message in messages) {

Source/PrivateHeaders/Ably/ARTJsonLikeEncoder.h

@@ -30,8 +30,8 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface ARTJsonLikeEncoder ()
 
-- (nullable ARTMessage *)messageFromDictionary:(NSDictionary *)input;
-- (nullable NSArray *)messagesFromArray:(NSArray *)input;
+- (nullable ARTMessage *)messageFromDictionary:(NSDictionary *)input protocolMessage:(nullable ARTProtocolMessage *)protocolMessage;
+- (nullable NSArray *)messagesFromArray:(NSArray *)input protocolMessage:(nullable ARTProtocolMessage *)protocolMessage;
 
 - (nullable ARTPresenceMessage *)presenceMessageFromDictionary:(NSDictionary *)input;
 - (nullable NSArray *)presenceMessagesFromArray:(NSArray *)input;

Source/include/Ably/ARTMessage.h

@@ -4,6 +4,41 @@
 #import <Ably/ARTTypes.h>
 #import <Ably/ARTChannelOptions.h>
 
+/**
+ * The namespace containing the different types of message actions.
+ */
+NS_SWIFT_SENDABLE
+typedef NS_ENUM(NSUInteger, ARTMessageAction) {
+    /**
+     * Message action has not been set.
+     */
+    ARTMessageActionUnset,
+    /**
+     * Message action for a newly created message.
+     */
+    ARTMessageActionCreate,
+    /**
+     * Message action for an updated message.
+     */
+    ARTMessageActionUpdate,
+    /**
+     * Message action for a deleted message.
+     */
+    ARTMessageActionDelete,
+    /**
+     * Message action for a newly created annotation.
+     */
+    ARTMessageActionAnnotationCreate,
+    /**
+     * Message action for a deleted annotation.
+     */
+    ARTMessageActionAnnotationDelete,
+    /**
+     * Message action for a meta-message that contains channel occupancy information.
+     */
+    ARTMessageActionMetaOccupancy,
+};
+
 NS_ASSUME_NONNULL_BEGIN
 
 /**
@@ -14,6 +49,19 @@ NS_ASSUME_NONNULL_BEGIN
 /// The event name, if available
 @property (nullable, readwrite, nonatomic) NSString *name;
 
+/// The action type of the message, one of the `ARTMessageAction` enum values.
+@property (readwrite, nonatomic) ARTMessageAction action;
+
+/// The version of the message, lexicographically-comparable with other versions (that share the same serial).
+/// Will differ from the serial only if the message has been updated or deleted.
+@property (nullable, readwrite, nonatomic) NSString *version;
+
+/// This message's unique serial (an identifier that will be the same in all future updates of this message).
+@property (nullable, readwrite, nonatomic) NSString *serial;
+
+/// The timestamp of the very first version of a given message.
+@property (nonatomic, nullable) NSDate *createdAt;
+
 /**
  * Construct an `ARTMessage` object with an event name and payload.
  *